Speed-change gears of motor vehicles are usually controlled and shifted by means of an actuating device arranged within reach of the driver. Actuating elements such as gearshift levers or selector levers, which are arranged, for example, between the front seats of the motor vehicle, are frequently used for this.
The design and ergonomic requirements imposed on such gearshift levers or selector levers are many and diverse. For example, to mediate a realistic feel of actuating the transmission to the driver, it is required for actuating devices of this class that these oppose the actuation with a certain resistance to motion, but continuous and smooth motion of the actuating element is nevertheless desired. At the same time, clear haptic and tactile feedback shall also be mediated to the driver, from which the river can intuitively infer the shifting operation performed during actuation.
Furthermore, it is also desirable to provide the driver with a clear optical feedback on the instantaneous state of the transmission or on the gear selected on the basis of the particular instantaneous position or angular position of the actuating elements, for example, of a selector lever. Against this background, a gear shifting gate, in the gates of which the gearshift or selector lever can move, is frequently arranged in the area of the gearshift or selector lever, and the gear shifting gate is usually provided with symbols or numbers in the sense of an unambiguous indication of the gear.
However, attention is also increasingly paid in the design of modern motor vehicles to the fact that actuating elements shall make do with a minimum of available installation space. Space is thus created for other components, on the one hand, and, on the other hand, the space available for the driver or passengers for moving can also be increased in this manner, without an increase in the dimensions of the vehicle being associated herewith. Another factor concerning the increasing size reduction especially of the actuating elements for vehicle transmissions is that modern gearboxes, but especially the current generations of automatic transmissions or automated motor vehicle transmissions, require only weak actuating forces, or are even controlled completely by means of actuators.
These, controlled by actuator devices, include especially the so-called “shift-by-wire” transmissions, in which there is usually no mechanical connection between the actuating element in the passenger compartment and the motor vehicle transmission itself any more. The shift commands are rather transmitted from the actuating device to the motor vehicle transmission mostly exclusively by means of electrical or electronic signals in the case of the example of the “shift-by-wire” transmissions. Thus, the need to transmit appreciable actuating forces or torques is thus eliminated from this side as well, and there is no longer a need to design bulky, long actuating elements or selector levers.
Concerning the design of actuating devices for motor vehicle transmissions, such developments consequently lead ultimately to the circumstance that actuating elements such as gear shift handle grips or selector levers are increasingly designed with smaller dimensions, reduced actuating forces as well as with shorter shifting paths.
Reductions in the space needed for installation and shortening of the shifting paths, in particular, often lead to the circumstance that a conspicuous gate contour or gearshift gate cannot be readily embodied any longer in the range in which a gear shift handle grip or selector lever is visible, because the motions of the gear shift handle grip or selector lever in the area of the gear shifting gate between two adjacent shift positions sometimes become smaller than the diameter of the lever arm due to the shorter shifting paths and the length of the lever, which is usually also reduced mainly because of considerations of the space available for installation.
Based on the fact that the relative motions are thus, on the whole, reduced in the area of the actuating elements for motor vehicle transmissions, reliable sensing of the instantaneous position of the selector lever becomes, moreover, increasingly difficult as well. Similar statements can also be made concerning haptics and ergonomics about the quality of the force-displacement curve of the locking of the selector lever, which cannot be readily ensured with the required quality as the dimensions and the angular motions of the selector lever become smaller.